1866165970243 has 2 divisors, whose sum is σ = 1866165970244. Its totient is φ = 1866165970242.

The previous prime is 1866165970237. The next prime is 1866165970283. The reversal of 1866165970243 is 3420795616681.

It is a weak prime.

It is an emirp because it is prime and its reverse (3420795616681) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1866165970243 is a prime.

It is a super-2 number, since 2×1866165970243² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1866165970283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 933082985121 + 933082985122.

It is an arithmetic number, because the mean of its divisors is an integer number (933082985122).

It is a 1-persistent number, because it is pandigital, but 2⋅1866165970243 = 3732331940486 is not.

Almost surely, 2^{1866165970243} is an apocalyptic number.

1866165970243 is a deficient number, since it is larger than the sum of its proper divisors (1).

1866165970243 is an equidigital number, since it uses as much as digits as its factorization.

1866165970243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13063680, while the sum is 58.

The spelling of 1866165970243 in words is "one trillion, eight hundred sixty-six billion, one hundred sixty-five million, nine hundred seventy thousand, two hundred forty-three".